docs: def max_min_projection(self, axis=2):
          """
          Compute maximum-minimum projection along a dimension.
  
          This computes the sum of the maximum and minimum values.
  
          Parameters
          ----------
          axis : int, optional, default = 2
              Which axis to compute projection along.
          """
          if axis >= size(self.value_shape):
              raise Exception('Axis for projection (%s) exceeds '
                              'image dimensions (%s-%s)' % (axis, 0, size(self.value_shape)-1))
  
          new_value_shape = list(self.value_shape)
          del new_value_shape[axis]
          return self.map(lambda x: amax(x, axis) + amin(x, axis), value_shape=new_value_shape)